New Defender's Study Bible Notes

11:1 substance. The word translated “substance” (Greek hupostasis), meaning “that which stands under”) is translated “person” in Hebrews 1:3. It means basically “the foundation.” Contrast apostasis (from which we derive “apostasy”), which means “that which stands away.” The term “hypostatic union,” meaning the union of God and man in Jesus Christ, comes from this word hupostasis. It refers to their “substantive,” or “foundational,” union.